ln.skyspot/session/HotspotVolume.cs

using System;
namespace skyspot.session
{
    public enum TrafficVolumeState { CREATED, ACTIVE, FULLFILLED, CANCELED }

    public class HotspotVolume
    {
        public DateTimeOffset Created;
        public DateTimeOffset FirstUse;

        public long TrafficVolume;
        public long UsedVolume;

        public long RemainingTrafficVolume => TrafficVolume - UsedVolume;

        public HotspotVolume()
        {
        }
    }
}